Why would taking a photo need to be part of a weather app? I would imagine that the main use of a weather app would be to check the weather. There may be one or two other apps that can already handle photos quite well.

I use WIFR Weather, the official weather app for one of my local TV stations, and one of a large number of station-branded weather apps by WSI Corporation which are all pretty much identical. It has the best maps out of any weather apps I've tried, though admittedly I haven't bothered to try anything else after finding it early last year, so for all I know AccuWeather or TWC stopped sucking like they did then.